Line a cupcake pan with cupcake liners and preheat the oven to 350 degrees F.
In a small bowl, add the sugar and zest. Rub the zest and sugar together with the tips of your fingers. Set aside.
In a mixing bowl whisk together the flour, baking powder, and baking soda together.
In the bowl of a stand mixer fitted with a paddle attachment, cream together the butter and the sugar/zest mixture until fluffy, about 3 minutes.
Add the eggs and vanilla and mix until well combined. Add the sour cream, and orange juice and mix until just combined.
Add the dry ingredients and mix until just combined.
Fill each cupcake liner ¾ cull of batter and bake for 19-22 minutes or until a toothpick comes out clean.
Remove from the oven and let cool in the tin on a wire cooling rack for 5 minutes before removing to cool out of the tin on the cooling rack. Don’t frost until completely cooled.
To make the frosting, in the bowl of a stand mixer whip the butter and cream cheese until light and fluffy.
Add the powdered sugar, orange juice/zest, and vanilla and mix on low until combined and then whip on medium-high speed for a few minutes.
Add the frosting to a piping bag with an open star tip and pipe swirls on top of the cupcakes. Garnish with a slice of orange and a sprinkle of zest.